Hello @nealumphred ,
The bug was due to the initial compression level. If you adjust the compression level beforehand, the bug won’t be triggered, and you won’t need to recompress all your images.
You can delete the converted version of an image and recompress it in the media library. If the new version is smaller than the previous one, we recommend recompressing all your images to ensure optimal results. We apologize for any inconvenience this may have caused.
Kind regards.